Persistence rate of cervical human papillomavirus infections and abnormal cytology in Rwanda

In this study, we determined the incidence and persistence of human papillomavirus (HPV) strains and of squamous intraepithelial lesions (SIL) or worse cytology in 237 HIV-positive and HIV-negative Rwandan women and whether the interleukin (IL)-28B single nucleotide polymorphism (SNP) at rs12979860 correlated with susceptibility to and persistence of HPV infection.

Cervical samples were collected at baseline and after 9, 18 and 24 months for a 40-HPV DNA screening test and a ThinPrep Pap test. Genotyping of the IL-28B SNP rs12979860 was performed using real-time polymerase chain reaction (PCR).

Chronic high-risk (HR) HPV infections occurred in 56% of HIV-positive women, while no HIV-negative women developed HPV chronicity. High-grade SIL (HSIL) or cancer was diagnosed in 38% of HIV-positive women with persistent HR-HPV infections. HIV and HR-HPV positivity at baseline were factors associated with an increased risk of HPV persistence. Additionally, HR-HPV positivity at baseline was associated with an increased risk of developing HSIL or worse cytology. The unfavourable T/x genotype at rs12979860 is common among Africans, and women with this genotype were found to be more commonly infected with HPV.

HPV screening in Rwanda may help to identify women at risk of developing cervical cancer and polymorphism in IL-28B may be associated with risk of contracting  HPV infection.